The South, 10-14 days, specific exclusions

I'm going to be travelling in the South with my girlfriend in Feb 2011. I will have been in India for a month before she meets me, and it is my third trip. It will be my girlfriend's second India trip (we went around the North the same time last year). I'm looking for suggestions on where the two of us should go in this limited time frame.

The thing is, I've been to the South before, and so have been to a bunch of places that I'm not planning to return to. So, I've been to Hampi, Panjim, Kochi, Ooty, Mysore, Pondi and Mamallapuram. I'm trying to construct a trip that avoids these places, but I'm having some difficulty - not least because some of these, particularly Ooty and Hampi, were absolutely sensational places to visit.

There are other limitations on our trip. I'm flying out of Mumbai at the end of the 10-14 days, so that must be the finishing point. Similarly, my girlfriend is flying in from SouthEast Asia - she can enter at Chennai, Bangalore, Trichy, Trivandrum or Kochi. We're on a low-mid budget. And neither of us wanna spend the whole time sitting on a beach, nor staying in the cities.

Other than that, we aren't really sure what we want to be doing. As are most travellers, we're looking for an authentic experience of South India, having some good food, conversations, markets, elephants, sites and surprises. I'd be really keen to hear any itinerary advice that anybody can provide, particularly interesting and unusual places in the South that are off the beaten track a little.

For what it's worth, the only fully-formed itinerary I've had in my mind is Trichy, Madurai, Rameshwaram and Cape Comorin (Kanyakumari). The temple complexes in Trichy and Madurai look sensational, and Rameshwaram and Cape Comorin are special places, the end of the line, apparently charming and small. Then get a long train to Mumbai, or perhaps even fly if budget permits. Other potentials include Munnar, housebout in Keralan backwaters, Belur/Halebidu, Kodaikanal.